They do look very similar. Main difference seems to be the arrangement of the air tanks/air pump. CR 103 had a large tank that ran on top of the usual running board and so they put another running board on top of the tank. The #20 has a large tank under the cab and another under the running board.
The magazine includes a shot of the 20 at the fairgrounds as you mentioned. As with the 103 it lost a lot of it's early character. I should have visited this one before I built my 375. Could have helped me out quite a bit. Oh no I might spark another models are a waste of time thread!
To stay on topic, I think that I am going to head over to the Morenci-Clifton area soon. I haven't yet visited the Porters even though they are fairly close. I guess there is also one on display in Safford. Too bad there isn't much of
anything left of the old inclines. Looks like it was quite an interesting setup at one time. Now just a bunch of big pits.